Ecosystems: OCR GCSE Biology A questions

Every OCR GCSE Biology A exam question on B4.1 Ecosystems, 2018–2025, with its mark scheme and examiner’s report.

All 169 questions on Ecosystems, as a list

June 2025, Paper 2 Foundation, Q19(a) (1 mark): Name the producer in this food web. [1]
June 2025, Paper 2 Foundation, Q19(b) (1 mark): At which two trophic levels are the carp feeding? Tick (3) two boxes. Primary consumer Secondary consumer Tertiary consumer [1]
June 2025, Paper 2 Foundation, Q19(c) (1 mark): Carp are large fish that have been introduced into America from Asia. Their numbers in lakes are rapidly increasing. Which reason explains why the number of car
June 2025, Paper 2 Foundation, Q19(d) (6 marks): The diagram shows a food web from a lake in America. trout shrimp dragonfly carp microscopic animals microscopic plants (d)* Carp feed at the bottom of the lake
June 2025, Paper 2 Foundation, Q23(c) (3 marks): The students write a conclusion for their experiment. Complete the students’ conclusion. Use words from the list. community compete differently efficiently equa
June 2025, Paper 4 Higher, Q10 (1 mark): The diagram shows how carbon is recycled in nature. Carbon dioxide 4 in the air Dead organic remains 3 1 2 Carbon compounds Carbon compounds in animals in plant
June 2025, Paper 4 Higher, Q12 (1 mark): The diagram shows the flow of biomass through a food chain. Trees Greenfly Ladybirds Blackbirds 2 × 107 kg / km2 2 × 104 kg / km2 2 × 103 kg / km2 400 kg / km2
June 2025, Paper 4 Higher, Q17(c) (3 marks): The students write a conclusion for their experiment. Complete the students’ conclusion. Use words from the list. community compete differently efficiently equa
June 2025, Paper 4 Higher, Q20(a) (2 marks): Explain why carp are described as feeding at two different trophic levels. Use details from the food web. [2]
June 2025, Paper 4 Higher, Q20(b) (1 mark): Carp are large fish that have been introduced into America from Asia. Their numbers in lakes have increased and they are becoming pests. Suggest a reason why th
June 2025, Paper 4 Higher, Q20(c) (4 marks): Carp feed at the bottom of lakes and this stirs up mud into the water. The mud contains minerals but makes the water cloudy. Explain two different effects that
June 2024, Paper 2 Foundation, Q1 (1 mark): Which process in the water cycle involves water moving from clouds to the ground? A Evaporation B Precipitation C Run off D Transpiration Your answer [1]
June 2024, Paper 2 Foundation, Q3 (1 mark): The diagram shows a food chain. Grass Grasshopper Snake 5000 kJ 500 kJ 100 kJ How much energy is lost between the producer and primary consumer? A 400 kJ B 4400
June 2024, Paper 2 Foundation, Q5 (1 mark): What is the definition of a population? A All the communities that live in a habitat. B All the different species living in a habitat. C All the members of one
June 2024, Paper 2 Foundation, Q14 (1 mark): Which row shows correct abiotic and biotic factors? Abiotic Biotic A food light intensity B food predators C pH of soil predators D temperature light intensity
June 2024, Paper 2 Foundation, Q20(a) (1 mark): Which term describes the mistletoe’s relationship with the tree? Put a ring around the correct option. mutualistic partner parasite predator prey [1]
June 2024, Paper 2 Foundation, Q22(a) (1 mark): State the name of one type of microorganism that can cause milk to decompose. [1]
June 2024, Paper 2 Foundation, Q22(b)(i) (1 mark): Suggest one piece of apparatus the students could use to keep the beaker of milk at a constant temperature. [1]
June 2024, Paper 2 Foundation, Q22(b)(ii) (1 mark): When milk decomposes, sugars in the milk are turned into lactic acid. To show how fast the milk decomposes, the students measure the time it takes for the pH to
June 2024, Paper 2 Foundation, Q24(a) (1 mark): How many secondary consumers are in this food web? [1]
June 2024, Paper 2 Foundation, Q24(b) (2 marks): Mongooses are described as both predators and competitors of St Lucia racers. Explain why. [2]
June 2024, Paper 2 Foundation, Q24(c) (1 mark): Biomass is lost as it passes through this food web. Put a ring around two ways that biomass is lost from this food web. egestion growth photosynthesis respirati
June 2024, Paper 2 Foundation, Q24(d)(ii) (1 mark): The mongooses soon spread throughout St Lucia. • Female mongooses can breed 3 times each year and produce 3 babies each time. • The St Lucia racer lays about 5
June 2024, Paper 2 Foundation, Q24(e)(i) (1 mark): Suggest why these snakes have survived on the island. [1]
June 2024, Paper 4 Higher, Q1 (1 mark): Which row shows correct abiotic and biotic factors? Abiotic Biotic A food light intensity B food predators C pH of soil predators D temperature light intensity
June 2024, Paper 4 Higher, Q3 (1 mark): All the living organisms and the place where they live is called … A A community B A habitat C A population D An ecosystem [1] Your answer
June 2024, Paper 4 Higher, Q4 (1 mark): Which processes in the carbon cycle return carbon to the atmosphere? A Decomposition and photosynthesis B Decomposition and respiration C Photosynthesis and fos
June 2024, Paper 4 Higher, Q16(a) (1 mark): How many secondary consumers are in this food web? [1]
June 2024, Paper 4 Higher, Q16(b) (2 marks): Mongooses are described as both predators and competitors of St Lucia racers. Explain why. [2]
June 2024, Paper 4 Higher, Q16(c) (1 mark): Biomass is lost as it passes through this food web. Put a ring around two ways that biomass is lost from this food web. egestion growth photosynthesis respirati
June 2024, Paper 4 Higher, Q16(d)(ii) (1 mark): The mongooses soon spread throughout St Lucia. • Female mongooses can breed 3 times each year and produce 3 babies each time. • The St Lucia racer lays about 5
June 2024, Paper 4 Higher, Q16(e)(i) (1 mark): Suggest why these snakes have survived on the island. [1]
June 2024, Paper 4 Higher, Q19(a) (1 mark): Put a ring around the term used to describe the tree in this relationship with the mistletoe. competitor host mutualistic partner prey [1]
June 2024, Paper 4 Higher, Q20(a) (2 marks): Explain why the students measured the pH of the milk. [2]
June 2024, Paper 4 Higher, Q20(b) (3 marks): Describe how the students should display their results in a graph. [3]
June 2024, Paper 4 Higher, Q20(c) (3 marks): Explain the effect of increasing the temperature on the decomposition of the milk in the experiment. [3]
June 2023, Paper 2 Foundation, Q1 (1 mark): Which process in the carbon cycle decreases the amount of carbon dioxide in the air? A Combustion B Decomposition C Photosynthesis D Respiration Your answer [1]
June 2023, Paper 2 Foundation, Q2 (1 mark): Which of these is a biotic factor that can affect the growth of plants? A Carbon dioxide levels B Light availability C Mineral content of the soil D Number of p
June 2023, Paper 2 Foundation, Q14 (1 mark): Which group will have the most organisms in any ecosystem? A Community B Population C Species D Trophic level Your answer [1]
June 2023, Paper 2 Foundation, Q15 (1 mark): Biomass is lost as it passes through a food chain. Which processes are responsible for this loss in biomass? A Egestion, excretion and respiration B Egestion, t
June 2023, Paper 2 Foundation, Q16(a) (2 marks): Fig. 16.2 shows a food web containing sorghum. Fig. 16.2 Snakes Humans Weaver birds Sorghum Write down the trophic level for each of these organisms in the food
June 2023, Paper 2 Foundation, Q19(b) (6 marks): (b)* Buddleia, a pest or a friend? Many people grow buddleia bushes in their gardens. Buddleia flowers attract butterflies that feed on nectar. Birds and bats f
June 2023, Paper 2 Foundation, Q22(a) (3 marks): Complete each sentence about decomposition. Decomposition is caused by microorganisms such as . The microorganisms use the process of to release the energy in d
June 2023, Paper 2 Foundation, Q22(b)(i) (1 mark): The pupils used the temperature of the compost heap as a measure of the rate of decomposition. Which statement explains why they could do this? Tick (3) one box
June 2023, Paper 2 Foundation, Q22(b)(ii) (1 mark): Which statement describes the results of the investigation? Tick (3) one box. High levels of carbon results in faster decomposition. If the carbon : nitrogen ra
June 2023, Paper 2 Foundation, Q22(b)(iii) (1 mark): Give one abiotic factor that the students should keep constant in their experiment. [1]
June 2023, Paper 2 Foundation, Q22(c) (3 marks): The table shows the mass of carbon and nitrogen in different plant materials. Mass of carbon per kg Mass of nitrogen per kg Plant material (g) (g) Fruit waste 1
June 2023, Paper 4 Higher, Q1 (1 mark): Which group will have the most organisms in any ecosystem? A Community B Population C Species D Trophic level Your answer [1]
June 2023, Paper 4 Higher, Q2 (1 mark): Biomass is lost as it passes through a food chain. Which processes are responsible for this loss in biomass? A Egestion, excretion and respiration B Egestion, t
June 2023, Paper 4 Higher, Q16(a) (3 marks): Complete each sentence about decomposition. Decomposition is caused by microorganisms such as . The microorganisms use the process of to release the energy in d
June 2023, Paper 4 Higher, Q16(b)(i) (1 mark): The pupils used the temperature of the compost heap as a measure of the rate of decomposition. Which statement explains why they could do this? Tick (3) one box
June 2023, Paper 4 Higher, Q16(b)(ii) (1 mark): Which statement describes the results of the investigation? Tick (3) one box. High levels of carbon results in faster decomposition. If the carbon : nitrogen ra
June 2023, Paper 4 Higher, Q16(b)(iii) (1 mark): Give one abiotic factor that the students should keep constant in their experiment. [1]
June 2023, Paper 4 Higher, Q16(c) (3 marks): The table shows the mass of carbon and nitrogen in different plant materials. Mass of carbon per kg Mass of nitrogen per kg Plant material (g) (g) Fruit waste 1
June 2023, Paper 4 Higher, Q20(a) (2 marks): Suggest why the colonisation of land by buddleia bushes has caused a decrease in the populations of other plants. [2]
June 2022, Paper 2 Foundation, Q1 (1 mark): The diagram shows a food web. Snake Owl Caterpillar Hawk Rabbit Grass Blue jay Grasshopper Which organisms are secondary consumers? A Blue jays and snakes B Cat
June 2022, Paper 2 Foundation, Q7 (1 mark): Which of these is a biotic factor that can affect organisms? A Light B pH of soil C Predators D Temperature Your answer [1]
June 2022, Paper 2 Foundation, Q9 (1 mark): Which process causes the loss of biomass from a food web? A Growth B Photosynthesis C Predation D Respiration Your answer [1]
June 2022, Paper 2 Foundation, Q12 (1 mark): Which is the order for the levels of organisation in an ecosystem, starting with the smallest? A community population organism ecosystem B ecosystem population
June 2022, Paper 2 Foundation, Q14 (1 mark): The diagram shows the energy trapped as biomass at each stage of a food chain. grass grasshopper mouse hawk 10 000 J 1000 J 200 J 40 J What is the percentage ef
June 2022, Paper 2 Foundation, Q20(a) (2 marks): The caterpillars eat pine trees. The caterpillars are eaten by birds such as cuckoos. The caterpillars are also parasitised by fungi. Draw a food web to show th
June 2022, Paper 2 Foundation, Q22(c) (3 marks): The gardener cuts the grass more often in the back garden. He thinks thistles grow better when he mows the grass more often. The diagram shows the grass lawns b
June 2022, Paper 2 Foundation, Q23(a) (1 mark): Why do the students make air holes in the bottle? Tick (✓) one box. To allow heat into the bottle. To allow oxygen gas into the bottle. To prevent the build-up
June 2022, Paper 2 Foundation, Q23(b)(i) (3 marks): Calculate the loss in mass per week of the bottle and plant waste with 16 air holes. Give your answer to 3 significant figures. Loss in mass = grams / week [3]
June 2022, Paper 2 Foundation, Q23(b)(ii) (2 marks): Describe the effect of the number of air holes on the rate of decomposition of the plant waste. [2]
June 2022, Paper 2 Foundation, Q23(b)(iii) (1 mark): The students checked that all the bottles and plant waste had a mass of 300 g at the start of the experiment. Explain why this helps the students to analyse the
June 2022, Paper 2 Foundation, Q23(b)(iv) (1 mark): What is the independent variable in the students’ investigation? [1]
June 2022, Paper 2 Foundation, Q23(b)(v) (2 marks): The students notice that during the experiment, water drips through the drain hole at the bottom of the apparatus on to the floor. Explain why this can produce
June 2022, Paper 4 Higher, Q1 (1 mark): The diagram shows the energy trapped as biomass at each stage of a food chain. grass grasshopper mouse hawk 10 000 J 1000 J 200 J 40 J What is the percentage ef
June 2022, Paper 4 Higher, Q5 (1 mark): What is the definition of a parasite? A An organism that kills another organism and then feeds from it. B An organism that kills another organism by out-competi
June 2022, Paper 4 Higher, Q16(c) (3 marks): The gardener cuts the grass more often in the back garden. He thinks thistles grow better when he mows the grass more often. The diagram shows the grass lawns b
June 2022, Paper 4 Higher, Q17(a) (1 mark): Why do the students make air holes in the bottle? Tick (✓) one box. To allow heat into the bottle. To allow oxygen gas into the bottle. To prevent the build-up
June 2022, Paper 4 Higher, Q17(b)(i) (3 marks): Calculate the loss in mass per week of the bottle and plant waste with 16 air holes. Give your answer to 3 significant figures. Loss in mass = grams / week [3]
June 2022, Paper 4 Higher, Q17(b)(ii) (2 marks): Describe the effect of the number of air holes on the rate of decomposition of the plant waste. [2]
June 2022, Paper 4 Higher, Q17(b)(iii) (1 mark): The students checked that all the bottles and plant waste had a mass of 300 g at the start of the experiment. Explain why this helps the students to analyse the
June 2022, Paper 4 Higher, Q17(b)(iv) (1 mark): What is the independent variable in the students’ investigation? [1]
June 2022, Paper 4 Higher, Q17(b)(v) (2 marks): The students notice that during the experiment, water drips through the drain hole at the bottom of the apparatus on to the floor. Explain why this can produce
June 2022, Paper 4 Higher, Q20(a) (2 marks): Draw a labelled pyramid of biomass for these feeding relationships showing the organisms at each level. [2]
November 2021, Paper 2 Foundation, Q1 (1 mark): The diagram shows the water cycle. X Lake Which process is X? A Evaporation B Precipitation C Run-off D Transpiration Your answer [1]
November 2021, Paper 2 Foundation, Q3 (1 mark): Which process causes the loss of biomass from food chains? A Growth B Photosynthesis C Predation D Respiration Your answer [1]
November 2021, Paper 2 Foundation, Q4 (1 mark): Tigers hunt and kill deer to eat. Which is the correct description of this relationship? A Competition B Mutualism C Parasitism D Predation Your answer [1]
November 2021, Paper 2 Foundation, Q6 (1 mark): A student measured the temperature in a compost heap and the temperature of the surrounding air. The graph shows the results. 60 50 Compost heap 40 Temperature
November 2021, Paper 2 Foundation, Q16(a)(i) (2 marks): Complete the sentences about the river and the organisms. You can use each word once, more than once, or not at all. community ecosystem habitat population The
November 2021, Paper 2 Foundation, Q16(a)(ii) (2 marks): Draw lines to connect each organism with its correct trophic level. Primary consumers Mayfly Producers Trout Secondary consumers Tertiary consumers [2]
November 2021, Paper 2 Foundation, Q22(c) (2 marks): Birds such as blackbirds make nests in hedges. Fig. 22.3 shows a food web that occurs in a hedge next to a field of wheat. Blackbirds Caterpillars Greenfly Whea
November 2021, Paper 4 Higher, Q2 (1 mark): Which row in the table gives the optimum conditions for decomposition? Oxygen Temperature (°C) Decomposers A Present 40 Present B Absent 10 Absent C Present 80
November 2021, Paper 4 Higher, Q3 (1 mark): The diagram shows the carbon cycle. Gas in the air X What is the importance of process X to living organisms? A It produces food containing carbon molecules. B
November 2021, Paper 4 Higher, Q4 (1 mark): The diagram shows the biomass in different trophic levels of a food chain. Oak tree 1000 kg Greenfly 10 kg Ladybirds 1 kg Which processes account for the decrea
November 2021, Paper 4 Higher, Q16(c) (2 marks): Birds such as blackbirds make nests in hedges. Fig. 16.3 shows a food web that occurs in a hedge next to a field of wheat. Blackbirds Caterpillars Greenfly Whea
November 2021, Paper 4 Higher, Q20(a) (2 marks): The young of Blandford flies live in rivers. They compete with mayflies for algae. Large fish called trout are predators of mayflies and Blandford flies. Comple
November 2021, Paper 4 Higher, Q20(b)(i) (1 mark): Suggest why the females show different feeding behaviour when they develop eggs. [1]
November 2021, Paper 4 Higher, Q20(d)(i) (1 mark): What name is given to the type of relationship shown by the fly and bacteria? [1]
November 2020, Paper 2 Foundation, Q1 (1 mark): The diagram shows part of a cycle in an ecosystem. Gas in the air Photosynthesis Combustion Respiration Decay Fossil fuel formation What is the name of the cycl
November 2020, Paper 2 Foundation, Q2 (1 mark): Goldfish are a species of fish. What name is given to all the goldfish living in a pond? A A community B An ecosystem C A habitat D A population Your answer [1]
November 2020, Paper 2 Foundation, Q4 (1 mark): This is a food chain for organisms in a forest. Oak tree Greenfly Ladybird Blackbird Which is the correct shape for a pyramid of biomass for this food chain? A
November 2020, Paper 2 Foundation, Q16(a)(i) (1 mark): Write down the number of trophic levels in this food web. [1]
November 2020, Paper 2 Foundation, Q16(a)(ii) (1 mark): What is the source of energy for this food web? [1]
November 2020, Paper 2 Foundation, Q16(a)(iii) (2 marks): Septoria fungus is a parasite of stevia. Explain what is meant by the term parasite. [2]
November 2020, Paper 2 Foundation, Q20(a) (1 mark): What do plant roots get from compost in the soil? Put a ring around the correct answer. carbon dioxide minerals nitrogen gas oxygen gas [1]
November 2020, Paper 2 Foundation, Q20(b) (2 marks): Compost can be made in a composting bin. In the bin aerobic bacteria turn dead plant material into compost. The drawing shows a composting bin. Explain why the
November 2020, Paper 2 Foundation, Q20(c) (1 mark): A new way of making compost is called bokashi. In this process the compost is made anaerobically in a different type of composter. Scientists compare the normal
November 2020, Paper 2 Foundation, Q20(d)(i) (3 marks): The scientists’ results for the normal compost are plotted on the grid. Complete the graph by plotting the results for the bokashi compost and draw a curve of b
November 2020, Paper 2 Foundation, Q20(d)(ii) (2 marks): Describe the change in the temperature of the normal compost during the investigation. [2]
November 2020, Paper 2 Foundation, Q20(d)(iii) (2 marks): Use data from Table 20.1 to calculate the difference between the maximum temperature of the normal compost and the maximum temperature of the bokashi compost. D
November 2020, Paper 2 Foundation, Q20(d)(iv) (2 marks): Which two statements explain this difference in temperature between the two types of compost? Tick (3) two boxes. Both types of compost are made by aerobic resp
November 2020, Paper 2 Foundation, Q20(e)(i) (3 marks): The mass of the normal compost has decreased by 19 kg per day. Calculate the decrease in mass of the bokashi compost per day. Give your answer to the nearest wh
November 2020, Paper 2 Foundation, Q22(a) (3 marks): Draw a line to the correct name for the three processes labelled A, B and C in Fig. 22.1. Evaporation A Photosynthesis Precipitation B Respiration Translocation
November 2020, Paper 2 Foundation, Q22(b) (1 mark): Surface run-off water passes through soil and back into the lake. Write down one reason why surface run-off water is important to organisms living in the lake.
November 2020, Paper 4 Higher, Q3 (1 mark): Which is the correct definition of a parasite? A An organism that is always at the top of a food chain. B An organism that kills and eats another organism. C An
November 2020, Paper 4 Higher, Q4 (1 mark): The diagram shows a food web in the sea. Squid Seal Seagull Krill Penguin Blue whale Plankton Not to scale The number of penguins decreased in the area. This ca
November 2020, Paper 4 Higher, Q14 (1 mark): The diagram shows pyramids of biomass for two food webs, X and Y. X Y Which statement explains the difference between the two pyramids? A In food web X there is
November 2020, Paper 4 Higher, Q16(a) (3 marks): Draw a line to the correct name for the three processes labelled A, B and C in Fig. 16.1. Evaporation A Photosynthesis Precipitation B Respiration Translocation
November 2020, Paper 4 Higher, Q16(b) (1 mark): Surface run-off water passes through soil and back into the lake. Write down one reason why surface run-off water is important to organisms living in the lake.
November 2020, Paper 4 Higher, Q18(a) (1 mark): Why do gardeners add compost to their soil? Tick (3) one box. Bacteria in the compost kill disease causing fungi. The compost is sterile and so is aseptic. The
November 2020, Paper 4 Higher, Q18(b) (2 marks): Compost can be made in a composting bin. In the bin aerobic bacteria turn dead plant material into compost. Some people use a different way of making compost, c
November 2020, Paper 4 Higher, Q18(c) (1 mark): Scientists investigate the two methods of making compost. This is their method: • Take one large pile of dead plant material • Divide the material into two samp
November 2020, Paper 4 Higher, Q18(d)(i) (5 marks): Plot the scientists’ results on the grid for normal and bokashi compost, and draw two curves of best fit. [5]
November 2020, Paper 4 Higher, Q18(d)(ii) (2 marks): Explain why the temperature of the compost in the normal bin changed as shown in the graph. [2]
November 2020, Paper 4 Higher, Q18(d)(iii) (2 marks): Explain the difference in the temperature changes between the aerobic normal compost and the anaerobic bokashi compost. [2]
November 2020, Paper 4 Higher, Q18(e)(i) (3 marks): The percentage decrease in the mass of the normal compost is 50%. Calculate the percentage decrease in the mass of the bokashi compost. Give your answer to 2 si
November 2020, Paper 4 Higher, Q18(e)(ii) (2 marks): The scientists concluded that the bokashi method of composting might be better for the environment. Use your answer from part (e)(i) to justify the scientists’
June 2019, Paper 2 Foundation, Q1 (1 mark): Which of these is an abiotic factor that can affect organisms? A Food availability B Light intensity C Pathogens D Predators Your answer [1]
June 2019, Paper 2 Foundation, Q2 (1 mark): The diagram shows the water cycle. B C A D Which label, A, B, C or D, represents evaporation? Your answer [1]
June 2019, Paper 2 Foundation, Q5 (1 mark): Which relationship describes an organism living on an animal and harming it? A Decomposition B Mutualism C Parasitism D Predation Your answer [1]
June 2019, Paper 2 Foundation, Q6 (1 mark): Most food chains only have a maximum of five trophic levels. Explain why. A Organisms always get larger at higher trophic levels. B Energy is lost at each troph
June 2019, Paper 2 Foundation, Q14 (1 mark): A student estimates the number of snails in a pond. Part of his method involves collecting snails and marking them. What is the name of the method he is using?
June 2019, Paper 2 Foundation, Q19(a) (1 mark): When the tide comes in, the salt marsh gets covered with seawater. Suggest one reason why salt marshes are difficult places for plants to grow. [1]
June 2019, Paper 2 Foundation, Q22(a)(i) (2 marks): Great tits are described as both primary consumers and secondary consumers. Explain why. [2]
June 2019, Paper 2 Foundation, Q22(a)(ii) (2 marks): Foxes are described as both predators and competitors of pine martens. Explain why. [2]
June 2019, Paper 2 Foundation, Q22(a)(iii) (1 mark): Which organism in the food web occupies the second trophic level? [1]
June 2019, Paper 2 Foundation, Q22(b)(i) (4 marks): Draw a bar chart on the graph paper to show the scientists’ results. The results for great tits and flycatchers should be on the same axis. [4]
June 2019, Paper 2 Foundation, Q22(b)(ii) (3 marks): The food web shows: • Weasels feed on great tits • Pine martens feed on flycatchers. Weasels live on the ground but pine martens live in trees. How can this be
June 2019, Paper 2 Foundation, Q23(a) (2 marks): The diagram shows the carbon cycle. carbon dioxide in air decomposition by 1 2 3 microbes carbon in waste and dead remains carbon in carbon sugars, stored in ca
June 2019, Paper 2 Foundation, Q23(b)(i) (2 marks): The scientists managed to grow crops in the soil. However on Mars, the minerals in the soil would soon run out. Explain why. [2]
June 2019, Paper 2 Foundation, Q23(b)(ii) (2 marks): Living organisms could be added to the soil but there is no air on Mars. The plants would need to be grown in an enclosed structure. At first, air would need to
June 2019, Paper 4 Higher, Q8 (1 mark): In food chains, biomass is lost between different trophic levels. One reason for this is the release of undigested food from the body. Which term is used to des
June 2019, Paper 4 Higher, Q16(a)(i) (2 marks): Great tits are described as both primary consumers and secondary consumers. Explain why. [2]
June 2019, Paper 4 Higher, Q16(a)(ii) (2 marks): Foxes are described as both predators and competitors of pine martens. Explain why. [2]
June 2019, Paper 4 Higher, Q16(a)(iii) (1 mark): Which organism in the food web occupies the second trophic level? [1]
June 2019, Paper 4 Higher, Q16(b)(i) (4 marks): Draw a bar chart on the graph paper to show the scientists’ results. The results for great tits and flycatchers should be on the same axis. [4]
June 2019, Paper 4 Higher, Q16(b)(ii) (3 marks): The food web shows: • Weasels feed on great tits • Pine martens feed on flycatchers. Weasels live on the ground but pine martens live in trees. How can this be
June 2019, Paper 4 Higher, Q17(a) (2 marks): The diagram shows the carbon cycle. carbon dioxide in air decomposition by 1 2 3 microbes carbon in waste and dead remains carbon in carbon sugars, stored in ca
June 2019, Paper 4 Higher, Q17(b)(i) (2 marks): The scientists managed to grow crops in the soil. However on Mars, the minerals in the soil would soon run out. Explain why. [2]
June 2019, Paper 4 Higher, Q17(b)(ii) (2 marks): Living organisms could be added to the soil but there is no air on Mars. The plants would need to be grown in an enclosed structure. At first, air would need to
June 2018, Paper 2 Foundation, Q1 (1 mark): Which process in the carbon cycle takes in carbon dioxide from the air? A Combustion B Decomposition C Photosynthesis D Respiration [1] Your answer
June 2018, Paper 2 Foundation, Q2 (1 mark): The diagram shows a pyramid of biomass. X Which trophic level is X? A Primary consumers B Producers C Secondary consumers D Tertiary consumers [1] Your answer
June 2018, Paper 2 Foundation, Q7 (1 mark): A scientist was studying a population of snails. He caught 60 snails in the first sample. He marked them and released them. He caught 50 snails in the second sa
June 2018, Paper 2 Foundation, Q10 (1 mark): A scientist is estimating the number of rabbits in a field. He has eight different estimates, 12, 12, 13, 15, 17, 19, 22 and 26. Which is the median value for h
June 2018, Paper 2 Foundation, Q19(a) (2 marks): The gardener wants valid results. Explain one factor that the gardener should keep constant. [2]
June 2018, Paper 2 Foundation, Q19(b)(i) (2 marks): Write down two differences between the change in temperature in Section A and the change in temperature in Section C. 1 2 [2]
June 2018, Paper 2 Foundation, Q19(b)(ii) (1 mark): The gardener decides that she should water all sections every week. Explain why she decides this. [1]
June 2018, Paper 2 Foundation, Q19(c) (2 marks): Each section of the composter has holes in it to let oxygen in. Explain why this helps the material to decay. [2]
June 2018, Paper 2 Foundation, Q21(a)(i) (1 mark): Calculate how much biomass is lost between the plants and humans. Answer = kg [1]
June 2018, Paper 2 Foundation, Q21(a)(ii) (1 mark): One way biomass is lost from the food chain is by insects eating the leaves of plants. Write down one other way that biomass is lost from the food chain. [1]
June 2018, Paper 2 Foundation, Q23(a) (1 mark): How many secondary consumers are shown in this food web? [1]
June 2018, Paper 2 Foundation, Q23(b) (2 marks): A survey was set up to see if the number of badgers and hedgehogs has changed in the UK. The number of badgers and hedgehogs were counted in different areas eac
June 2018, Paper 2 Foundation, Q23(c)(i) (2 marks): In country areas, where badgers live, this is an advantage to the hedgehogs. In cities, where there are many roads, this is a disadvantage. Explain these two co
June 2018, Paper 2 Foundation, Q24(a) (5 marks): Plot a graph of the student’s results and draw a line of best fit. [5]
June 2018, Paper 2 Foundation, Q24(b) (4 marks): The student thinks that shade from the tree is affecting the plants. Explain how the student’s results show this. [4]
June 2018, Paper 4 Higher, Q16(a) (1 mark): How many secondary consumers are shown in this food web? [1]
June 2018, Paper 4 Higher, Q16(b) (2 marks): A survey was set up to see if the number of badgers and hedgehogs has changed in the UK. The number of badgers and hedgehogs were counted in different areas eac
June 2018, Paper 4 Higher, Q16(c)(i) (2 marks): In country areas, where badgers live, this is an advantage to the hedgehogs. In cities, where there are many roads, this is a disadvantage. Explain these two co
June 2018, Paper 4 Higher, Q17(a) (5 marks): Plot a graph of the student’s results and draw a line of best fit. [5]
June 2018, Paper 4 Higher, Q17(b) (4 marks): The student thinks that shade from the tree is affecting the plants. Explain how the student’s results show this. [4]
June 2018, Paper 4 Higher, Q20(a) (3 marks): Which size of plant pieces is best for making compost? Explain your answer. [3]
June 2018, Paper 4 Higher, Q20(b) (2 marks): The size of the plant pieces has an effect on the number of microorganisms in the compost. Suggest why. [2]
June 2018, Paper 4 Higher, Q20(c) (3 marks): The decomposition of dead plants and animals is an important process for ecosystems. Explain why. [3]
June 2018, Paper 4 Higher, Q23(a)(i) (2 marks): Calculate the percentage efficiency of transfer of biomass between the cattle food crop and humans. Answer = % [2]
June 2018, Paper 4 Higher, Q23(a)(ii) (2 marks): Write down two ways that biomass is lost from the food chain. 1 2 [2]

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